The present invention relates to a wireless computer controlled system for automatically loading and unloading articles from a store unit, and for transporting them into a work area, by means of which it is possible to programmably control the operation of store and of computer controlled self-powered vehicles or trolleys to fully free the system from the need for intervention by any operator.
The automated operation of large store units by means of computerised systems, provided with automatic loading and unloading devices, is in itself known and in use from many time. These automatic store units, both from the structural and from their operational point of view, have nevertheless been designed and constructed as functionally independent systems which cannot be integrated with modern production processes requiring automatic operations integrated with services and other functions on which they generally depend.
Current automated stores are therefore composed of large structures located in isolated areas, often far from the work areas, so that they require conveying systems for moving materials or articles from a store unit to a working area or machine tool. Automated store units and conveying systems using computer-controlled and self-powered vehicles moving along a travelling path are known for example from GB-A- 2,174,686 or U.S. Pat. No. 4,538,950; nevertheless although the management of the store unit and running of conveying vehicles may be controlled by a central processing unit, they require large storing areas and do not allow to change or modify the working program of the storage unit, unless from the central unit, to adapt to working requirements each time they occur. Therefore a complex and costly wire system is required for connecting and transmitting separate program data from the central control unit, to the store units to the vehicles and to the working points. U.S. Pat. No. 4,669,047 suggest the use of computer-controlled, self-powered vehicles provided with loading means for an automated supply system, in which storage modules are used as passive back-up supply source movable on the same transporting vehicles of the system; no possibility exist to actively and independently modify the management program of the storage modules by an operator, unless from a central control unit.
Rotary stores are also know which advantageously comprise a rack type supporting structure, small in size, suitable for being placed inside a work area to be served. Although management of these stores is both generally automated and linked to a specific software, it nevertheless requires the intervention of an operator for loading and unloading articles or objects stored, which have to be removed or stored manually or by mechanical means actuated in any way by an operator, who each time must cause the rotation of the rack to select the required shelf, acting on a control keyboard on the same store unit.
From EP-A-110547 it is known a handling and storage system suitable for operating, in an integrated manner, with a transport system inside a work area.
According to this document self-powered vehicles are travelling around a tracking network to stop near a vertically extending storing rack; the rack storing device is computer-controlled to rotate and to stop selected shelves at the same level as a programmed vehicle arrives at the particular storage location. The vehicle is provided with a pick-up device to load or unload articles from the selected shelf. This arrangement therefore comprises different parts which co-operate with each other, but which are separately controlled to select and to gain access to a particular storing area of the store unit; therefore a central program unit must separately feed co-related program data to the vehicle and to the storage unit by suitable wire connections or network.